CN1380250A - Double mesopore molecular sieve and its preparation method - Google Patents
Double mesopore molecular sieve and its preparation method Download PDFInfo
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- CN1380250A CN1380250A CN 02102264 CN02102264A CN1380250A CN 1380250 A CN1380250 A CN 1380250A CN 02102264 CN02102264 CN 02102264 CN 02102264 A CN02102264 A CN 02102264A CN 1380250 A CN1380250 A CN 1380250A
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Abstract
The present invention relates to a double-mesopore molecular sieve and its preparation method, belonging to the field of chemical synthesis technology, and is characterized by that the double-pore pore size distributions of said material are being in the mesopore zone, so that said material can effectively meet the requirements to the catalyst pore size distribution for macromolecualr shape selection and diffusion effect, and is a potential industrial catalyst and catalyst carrier. Its preparation method uses quaternary ammonium salt cationic surfactant as template agent, and in the weak alkaline system utilizes the room-temp. hydrolysis and condensation polymerization of ethyl metasilicate to synthesize the invented double-mesopore distribution molecular sieve.
Description
One, technical field
A kind of double mesopore molecular sieve of the present invention and preparation method thereof, synthetic and the synthetic method that belongs to a kind of chemical substance, relating to the category of inorganic synthetic and catalytic science, specifically is a kind of new catalyzer and the synthetic and corresponding new synthetic method of carrier thereof.
Two, background technology
Along with petrochemical complex, fine chemistry industry further deeply and Coal Chemical Industry flourish, it is also more and more to relate to macromolecular catalyzed reaction, this just requires the geometric diameter in catalyst pores road must be greater than the effective power diameter of these molecules, and traditional zeolite molecular sieve is because the limitation in its aperture has been difficult in the positive effect of this field performance.Researchist's reported first of U.S. Mobil company in 1992 use C
nH
2n+1NMe
3Br (n＞6) type cats product is made the synthetic M41S type mesopore molecular sieve of template, because its high specific surface area, big pore volume and regular mesopore orbit, and but its aperture nationality changes synthesis condition and characteristics such as is regulated, and at absorption, separation, new high-tech material, particularly the development field at new catalytic material demonstrates huge and the potential prospects for commercial application.Yet, the result of research shows both at home and abroad at present, the aperture of mesopore molecular sieve all is monodrome and distributes, it can solve the difficult problem of macromole shape selective catalysis well, but the actual industrial process feedack shows, reactant or the diffusion of product molecule in catalyst surface and the duct controlled step of this process often in the macromolecular reaction.If reaction product can not in time spread, and around active sites secondary cracking takes place, then can cause and optionally obviously reduce, i.e. the preparation of bulky molecular catalysis cracking catalyst often needs the reasonable disposition in two-stage hole or multistage hole.Therefore will have even more important theory and practical meaning if can directly synthesize meso-porous molecular sieve material with the reasonable distribution in two-stage hole or multistage hole.Prior art (patent publication No.: CN1304871A and CN1304872A) is utilized nonionogenic tenside to make template and is obtained a kind of diplopore molecular sieve through silicon source hydrolytic condensation, but its building-up process needs to do the silicon source with two kinds of silicoorganic compound, easily environment is polluted, and need the treatment step of relative complex and long reaction times, the pore size distribution of gained diplopore molecular sieve lays respectively at mesoporous district and big porose area, and pore distribution is broad also.
Three, summary of the invention
The purpose of this invention is to provide a kind of have narrow two mesoporous pore size distribution features and constitutionally stable double mesopore molecular sieve material and preparation method thereof, thus for solve the macromole shape selective catalysis and effectively the requirement of diffusion couple catalyzer or support of the catalyst pore size distribution new material is provided.
A kind of double mesopore molecular sieve of the present invention is characterized in that the diplopore pore size distribution that had all in mesoporous zone, and its concrete feature is as follows:
Elementary mesoporous aperture is: 2.5-3.2nm,
Pore volume is: 0.4-0.76cm
3/ g,
Specific surface area is: 600-1107m
2/ g;
Secondary mesoporous aperture is: 8-46nm,
Pore volume is: 0.46-1.94cm
3/ g,
Specific surface area is: 138-243m
2/ g.
Described double mesopore molecular sieve typically has the perfect adaptation (Fig. 5) in six sides or cylindrical hole and cestode shape hole, the N of its feature
2There is the crooked flex point (Fig. 1 and Fig. 6) that significantly causes owing to the capillary condensation effect in adsorption isothermal line in 0.2-0.4 and two relative pressure intervals of 0.8-1.0.
The preparation method of above-mentioned a kind of double mesopore molecular sieve, it is characterized in that, with Tetradecyl Trimethyl Ammonium Bromide (TTAB), cetyl trimethylammonium bromide (CTAB) and octadecyl trimethylammonium bromide (OTAB) are respectively as template, tetraethoxy (TEOS) is the silicon source, at first cats product is dissolved in the distilled water, be stirred to dissolving fully, under agitation drip tetraethoxy then, be stirred to and mix, the solubility promoter sym-trimethylbenzene (TMB) that can add appropriate amount according to the needs of aperture modulation, follow dropping ammonia under agitation, sodium hydroxide solution, tetraethyl ammonium hydroxide (TEAOH) solution at room temperature continues to stir after 1-6 hour centrifuge washing, the oven dry after grind the former powder of synthesis type, the roasting in air atmosphere of the former powder of synthesis type is got final product, and when reaction conditions is as follows for its various materials:
Alkyl trimethyl ammonium bromide [C
nH
2n+1NMe
3Br] in n=14,16,18;
The mol ratio of reactant feed is:
SiO
2∶0.185TTAB∶0.18NH
3·H
2O∶100H
2O
SiO
2∶0.185CTAB∶0.05Na
2O(or?0.06?TEAOH)∶100H
2O
SiO
2∶0.185CTAB∶0.6NH
3·H
2O∶(0-0.32)TMB∶100H
2O
xSiO
2∶yCTAB∶zNH
3·H
2O∶wH
2O
1≤x≤3,0.062≤y≤0.185,0.2≤z≤0.6,25≤w≤125 wherein;
SiO
2∶0.185OTAB∶0.6NH
3·H
2O∶100H
2O
The concentration of CTAB is 3.2-9.6wt%;
The mol ratio of CTAB and silicon is 0.062-0.185;
Above-mentioned a kind of method for preparing double mesopore molecular sieve is characterized in that, alkyl quaternary ammonium salts template C
nH
2n+1NMe
3N=16 among the Br, 18 is better.
Above-mentioned a kind of method for preparing double mesopore molecular sieve is characterized in that when CTAB concentration was 3.2wt%, the mol ratio of CTAB and silicon was better with 0.062-0.185.
Above-mentioned a kind of method for preparing double mesopore molecular sieve is characterized in that the concentration of CTAB is better with 3.2-9.6wt% when the mol ratio of CTAB and silicon is 0.185.
Above-mentioned a kind of method for preparing double mesopore molecular sieve is characterized in that synthesis temperature with room temperature-40 ℃, and the reaction times is better with 1-6 hour.
Above-mentioned a kind of method for preparing double mesopore molecular sieve is characterized in that also can adding the organic cosolvent sym-trimethylbenzene in the synthetic system when CTAB is used as template, and its concentration is better with 0-1.8wt%.
Above-mentioned a kind of method for preparing double mesopore molecular sieve is characterized in that alkali source can be ammoniacal liquor, sodium hydroxide solution or tetraethyl ammonium hydroxide solution when CTAB is used as template.
Cats product when characteristics of the present invention are with the single mesoporous distribution molecular sieve of common preparation is made template, set of dispense ratio by the modulation reaction system, at room temperature synthetic fast meso-porous molecular sieve material with two mesoporous distribution characteristicss, enriched the kind of meso-porous molecular sieve material, the aperture of designing catalyzer for orientation is selected the shape ability and is improved the diffusion place new opportunity is provided.
Characteristics of the present invention also are and can regulate two mesoporous pore size distributions according to the actual needs of Catalyst Design.Characterization result from product, the product that the inventive method obtains has narrow two mesoporous distribution, it is the elementary mesoporous and secondary mesoporous perfect adaptation of cestode shape of a kind of six sides or round shape, visible its good thermal stability from hot analytical results, a kind of really simple to operate, well behaved double mesopore molecular sieve and synthetic novel method thereof.
This synthetic method mild condition, simple to operate, clean soon.Compared with the prior art, so characteristics of the present invention are preparing double mesopore molecular sieve with cats product as template; Characteristics of the present invention also are to synthesize carries out in the system of single silicon source; Characteristics of the present invention are that also building-up process can at room temperature finish fast, and are convenient, clean soon; Characteristics of the present invention also are scope that the synthetic double mesopore molecular sieve has narrow pore size distribution and a pore size distribution all in mesoporous zone, are a kind ofly can satisfy macromole simultaneously and select new catalyst or the catalyst support material that shape and diffusional effect distribute and require catalyst pores.
Four, description of drawings
Fig. 1 is to be the feature N of template synthetic double mesopore molecular sieve after roasting with TTAB
2The adsorption-desorption thermoisopleth.
Fig. 2 is to be the characteristic aperture distribution plan of template synthetic double mesopore molecular sieve after roasting with TTAB.
Fig. 3 is to be characteristic X-ray diffraction (XRD) figure of template synthetic double mesopore molecular sieve after roasting with CTAB.
Fig. 4 is to be the template synthetic double mesopore molecular sieve high explanation Electronic Speculum of the feature after roasting (TEM) figure with CTAB.
Fig. 5 is to be the feature thermogravimetric-differential thermal analysis result of template synthetic double mesopore molecular sieve with CTAB.
Fig. 6 is to be the feature N of template synthetic double mesopore molecular sieve after roasting with CTAB
2The adsorption-desorption thermoisopleth.
Fig. 7 is to be the characteristic aperture distribution plan of template synthetic double mesopore molecular sieve after roasting with CTAB.
Five, embodiment
Further describe feature of the present invention below by example.Example 1:
Under constant agitation speed, a certain amount of tetraethoxy is dropwise added in the aqueous solution that is dissolved with tensio-active agent TTAB, continue to stir 5 minutes, mix to mixture, under agitation dropwise drip the strong aqua of specified rate then, making the pH of system is 9.5, obtains mole and consists of SiO
2: 0.185TTAB: 0.18NH
3H
2O: 100H
2The mixture of O.With this mixture after room temperature continue to stir 6 hours, the centrifugation washing, oven dry after grind the synthesis type double mesopore molecular sieve.In air atmosphere, be warming up to 550 ℃ of roastings 6 hours gradually, promptly get double mesopore molecular sieve.Its typical N that gets
2Adsorption-desorption thermoisopleth and corresponding pore distribution curve such as Fig. 1.Example 2:
Under constant agitation speed, CTAB is soluble in water with certain amount of surfactant, intensification (30-40 ℃) is dissolved CTAB fully slightly becomes even clear soln, under agitation dropwise add quantitative tetraethoxy in the CTAB solution then, continue to stir 5 minutes, and mixed to mixture, under agitation dropwise drip the strong aqua of specified rate at last, making the pH of system is 9.5, obtains mole and consists of SiO
2: 0.185CTAB: 0.6NH
3H
2O: 100H
2The mixture of O.With this mixture after room temperature-40 ℃ continues to stir 6 hours, the centrifugation washing, oven dry after grind the synthesis type double mesopore molecular sieve.In air atmosphere, be warming up to 550 ℃ of roastings 6 hours gradually, promptly get double mesopore molecular sieve.Its typical X RD figure, TEM photo, N
2Adsorption-desorption thermoisopleth and mutually deserved pore distribution curve and hot analytical results are respectively as Fig. 2-5.Example 3:
Under constant agitation speed, CTAB is soluble in water with certain amount of surfactant, intensification (30-40 ℃) makes CTAB be dissolved into even clear soln fully slightly, then quantitative tetraethoxy is under agitation dropwise added in the CTAB solution, continue to stir 5 minutes, add quantitative solubility promoter sym-trimethylbenzene (TMB) again, being stirred to mixture mixes, the last strong aqua that under agitation dropwise drips specified rate, making the pH of system is 9.5, obtains mole and consists of SiO
2: 0.185CTAB: 0.32TMB: 0.6NH
3H
2O: 100H
2The mixture of O.With this mixture after room temperature-40 ℃ continues to stir 6 hours, the centrifugation washing, oven dry after grind the synthesis type double mesopore molecular sieve.In air atmosphere, be warming up to 550 ℃ of roastings 6 hours gradually, promptly get double mesopore molecular sieve.
Claims (9)
1. double mesopore molecular sieve is characterized in that the diplopore pore size distribution that had all in mesoporous zone, and its concrete feature is as follows:
Elementary mesoporous aperture is: 2.5-3.2nm,
Pore volume is: 0.4-0.76cm
3/ g,
Specific surface area is: 600-1107m
2/ g;
Secondary mesoporous aperture is: 8-46nm,
Pore volume is: 0.46-1.94cm
3/ g,
Specific surface area is: 138-243m
2/ g.
2. a kind of double mesopore molecular sieve according to claim 1 is characterized in that described double mesopore molecular sieve has the perfect adaptation in six sides or garden cylindrical hole and strip hole, its N
2There is the crooked corner feature that significantly causes owing to the capillary condensation effect in adsorption isothermal line in 0.2-0.4 and two relative pressure intervals of 0.8-1.0.
3. the preparation method of above-mentioned a kind of double mesopore molecular sieve, it is characterized in that, with Tetradecyl Trimethyl Ammonium Bromide (TTAB), cetyl trimethylammonium bromide (CTAB) and octadecyl trimethylammonium bromide (OTAB) are respectively as template, tetraethoxy (TEOS) is the silicon source, at first cats product is dissolved in the distilled water, be stirred to dissolving fully, under agitation drip tetraethoxy then, be stirred to and mix, the solubility promoter sym-trimethylbenzene (TMB) that can add appropriate amount according to the needs of aperture modulation, follow dropping ammonia under agitation, sodium hydroxide solution, tetraethyl ammonium hydroxide (TEAOH) solution, at room temperature continue to stir after 1-6 hour, centrifuge washing, oven dry after grind the former powder of synthesis type, the roasting in air of the former powder of synthesis type is got final product, and when reaction conditions is as follows for its various materials:
Alkyl trimethyl ammonium bromide [C
nH
2n+1NMe
3Br] in n=14,16,18;
The mol ratio of reactant feed is:
SiO
2∶0.185TTAB∶0.18NH
3·H
2O∶100H
2O
SiO
2∶0.185CTAB∶0.05Na
2O(or?0.06?TEAOH)∶100H
2O
SiO
2∶0.185CTAB∶0.6NH
3·H
2O∶(0-0.32)TMB∶100H
2O
xSiO
2∶yCTAB∶zNH
3·H
2O∶wH
2O
1≤x≤3,0.062≤y≤0.185,0.2≤z≤0.6,25≤w≤125 wherein;
SiO
2∶0.185OTAB∶0.6NH
3·H
2O∶100H
2O
The concentration of CTAB is 3.2-9.6wt%;
The mol ratio of CTAB and silicon is 0.062-0.185;
4. a kind of method for preparing double mesopore molecular sieve according to claim 3 is characterized in that, alkyl quaternary ammonium salts template C
nH
2n+1NMe
3N=16 among the Br, 18 is better.
5. a kind of method for preparing double mesopore molecular sieve according to claim 3 is characterized in that when CTAB concentration was 3.2wt%, the mol ratio of CTAB and silicon was better with 0.062-0.185.
6. a kind of method for preparing double mesopore molecular sieve according to claim 3 is characterized in that the concentration of CTAB is better with 3.2-9.6wt% when the mol ratio of CTAB and silicon is 0.185.
7. a kind of method for preparing double mesopore molecular sieve according to claim 3 is characterized in that synthesis temperature with room temperature-40 ℃, and the reaction times is better with 1-6 hour.
8. a kind of method for preparing double mesopore molecular sieve according to claim 3 is characterized in that also can adding the organic cosolvent sym-trimethylbenzene in the synthetic system when CTAB is used as template, and its concentration is better with 0-1.8wt%.
9. a kind of method for preparing double mesopore molecular sieve according to claim 3 is characterized in that alkali source can be ammoniacal liquor, sodium hydroxide solution or tetraethyl ammonium hydroxide solution when CTAB is used as template.
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004080895A1 (en) * | 2002-12-30 | 2004-09-23 | Nanomaterials Technology Pte Ltd. | Mesoporous silica materials and its preparation |
| CN1298625C (en) * | 2005-01-10 | 2007-02-07 | 山西大学 | Double metaporous silicon dioxide material and its preparing method |
| CN1314589C (en) * | 2004-09-24 | 2007-05-09 | 中国石油化工股份有限公司 | Porous material and its synthesis method |
| CN100417324C (en) * | 2004-05-14 | 2008-09-10 | 北京化工大学 | Compsn. of agricultural pesticide and preparation method |
| CN101733085B (en) * | 2009-11-27 | 2011-08-10 | 辽宁石油化工大学 | Zirconium-aluminium double-mesoporous material and preparation method thereof |
| CN102942721A (en) * | 2012-10-26 | 2013-02-27 | 武汉工程大学 | Nanometer white carbon black reinforced styrene-butadiene rubber composite material preparation process |
| CN104261414A (en) * | 2014-09-25 | 2015-01-07 | 太原理工大学 | Synthesis method of bimodal mesoporous silicon dioxide |
| CN104854029A (en) * | 2012-10-01 | 2015-08-19 | 陶氏环球技术有限公司 | Compositions and processes for synthesizing cubic mesoporous silicas having "noodle-like" morphology |
| CN105540608A (en) * | 2014-11-03 | 2016-05-04 | 中国石油化工股份有限公司 | Y-Beta composite molecular sieve having double mesoporous structure, and preparation method thereof |
| CN111085208A (en) * | 2018-10-24 | 2020-05-01 | 中国石油化工股份有限公司 | Non-noble metal low-carbon alkane dehydrogenation catalyst with spherical double-mesoporous composite carrier and preparation method and application thereof |
| CN118495546A (en) * | 2024-07-18 | 2024-08-16 | 山东固立特新材料科技有限公司 | Mesoporous silica material with oversized opening and preparation method thereof |
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2002
- 2002-01-30 CN CNB02102264XA patent/CN1151065C/en not_active Expired - Fee Related
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2004080895A1 (en) * | 2002-12-30 | 2004-09-23 | Nanomaterials Technology Pte Ltd. | Mesoporous silica materials and its preparation |
| CN100417324C (en) * | 2004-05-14 | 2008-09-10 | 北京化工大学 | Compsn. of agricultural pesticide and preparation method |
| CN1314589C (en) * | 2004-09-24 | 2007-05-09 | 中国石油化工股份有限公司 | Porous material and its synthesis method |
| CN1298625C (en) * | 2005-01-10 | 2007-02-07 | 山西大学 | Double metaporous silicon dioxide material and its preparing method |
| CN101733085B (en) * | 2009-11-27 | 2011-08-10 | 辽宁石油化工大学 | Zirconium-aluminium double-mesoporous material and preparation method thereof |
| CN104854029A (en) * | 2012-10-01 | 2015-08-19 | 陶氏环球技术有限公司 | Compositions and processes for synthesizing cubic mesoporous silicas having "noodle-like" morphology |
| CN104854029B (en) * | 2012-10-01 | 2017-03-29 | 陶氏环球技术有限公司 | The composition and method of cubic mesoporous silica silicon of the synthesis with " noodles shape " form |
| US9452416B2 (en) | 2012-10-01 | 2016-09-27 | Dow Global Technologies Llc | Compositions and processes for synthesizing cubic mesoporous silicas having “noodle-like” morphology |
| CN102942721B (en) * | 2012-10-26 | 2014-10-15 | 武汉工程大学 | Nanometer white carbon black reinforced styrene-butadiene rubber composite material preparation process |
| CN102942721A (en) * | 2012-10-26 | 2013-02-27 | 武汉工程大学 | Nanometer white carbon black reinforced styrene-butadiene rubber composite material preparation process |
| CN104261414B (en) * | 2014-09-25 | 2016-01-20 | 太原理工大学 | A kind of synthetic method of double-mesopore silicon dioxide |
| CN104261414A (en) * | 2014-09-25 | 2015-01-07 | 太原理工大学 | Synthesis method of bimodal mesoporous silicon dioxide |
| CN105540608A (en) * | 2014-11-03 | 2016-05-04 | 中国石油化工股份有限公司 | Y-Beta composite molecular sieve having double mesoporous structure, and preparation method thereof |
| CN111085208A (en) * | 2018-10-24 | 2020-05-01 | 中国石油化工股份有限公司 | Non-noble metal low-carbon alkane dehydrogenation catalyst with spherical double-mesoporous composite carrier and preparation method and application thereof |
| CN118495546A (en) * | 2024-07-18 | 2024-08-16 | 山东固立特新材料科技有限公司 | Mesoporous silica material with oversized opening and preparation method thereof |
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